Latch for adjusting worm of a movable jaw wrench



Oct. 8, 1957 1 J, FERCANA} 2,808,751

LATCH FOR ADJUSTING WORM OF A MOVABLE JAW WRENCH Filed Nov. 9, 1956 U FIG. 2

FIG. 3

INVENTOR. JAMES E. FERCANA ATTORNEY United States Patent p A, 2,808,751 LATCH FOR remains woRM or A MOVABLE JAW R NCH V James E. Fercana;near North'Ja'ckson, Ohio Application November 9, 1956, Serial No. 621,248

2 Claims. (Cl. 81-165) This invention relates to an adjustable wrench and more particularly to a lock structure incorporated with a movable jaw Wrench whereby the movable jaw will be held in desired adjustment.

The principal object of the invention is the provision of a lock for a movable jaw wrench which will hold the adjustment worm of the wrench and the movable jaw thereof in fixed location.

A further object of the invention is the provision of a movable jaw wrench having a simple lock mechanism positioned adjacent the adjustment worm thereof whereby said adjustment worm may be held against rotation.

A still further object of the invention is the provision of an adjustable wrench of the crescent type having a spring urged locking button positioned transversely of the same adjacent the adjustment worm and adapted to so engage said adjustment worm as to hold it against rotation and at the same time be manually movable to disengaged position.

It is well known that adjustable wrenches, commonly called crescent wrenches, have been objected to becaused the movable jaw will not hold its adjustment and there is consequently the need for repeatedly correcting the adjustment which is time consuming and annoying to the workman using the wrench. Various constructions have been devised in an effort to solve this problem, such as those set forth in the prior art, but none has been adopted commercially. The several constructions of the prior art are expensive and difiicult to install and, more importantly, they are difiicult to operate.

The present disclosure eliminates these objections. The device is very inexpensive, can be easily installed in the wrench and is easily operated by the natural and normal hand movements of the workman holding the movable jaw wrench.

With the foregoing and other objects in view which will appear as the description proceeds, the invention resides in the combination and arrangement of parts and in the details of construction hereinafter described and claimed, it being the intention to cover all changes and modifications of the example of the invention herein chosen for purposes of the disclosure, which do not constitute departures from the spirit and scope of the invention.

The invention is illustrated in the accompanying draw- .ing, wherein:

Figure l is a perspective view of one side of a movable jaw wrench showing the lock device thereon.

Figure 2 is a perspective view of the other side of the wrench showing the operating portion of the lock device.

Figure 3 is an enlarged cross section of a portion of a movable jaw wrench showing the lock device in position therein.

By referring to the drawing and Figures 1 and 2 in particular it will be seen that a movable jaw wrench is disclosed which comprises a handle portion having an angularly disposed fixed jaw 11 and an adjustably 2 v positioned movable jaw 12. Theadjustably positioned movable jaw 12 is slidably mounted in a channel 13 formed in a widened portion 14'of the wrench disposed between the handle 10 and the fixed jaw 11'.

The lower edge of the movable jaw 12 which is disposed in the channel 13 is provided with a rack 15 so that it may be moved by a worm 16 which is mounted in an'opening '17 in the widened portioii14 of the wrench; The worm 16 is rotatably positionedin the opening 17, as known in the art, and the spiral"thread pattern-thereo'f directly engages the rack of 15 of the movable jaw 12, as also known in the art. The outermost peripheral edges of the spiral thread pattern of the worm 16 are knurled, as best shown in Figure 3 of the drawing, the knurling being indicated by the numeral 18.

The lock device of the wrench is positioned adjacent the Worm 16 in an opening 19 formed therethrough, a portion 20 of the opening being of greater diameter than the remainder thereof. The opening 19 is positioned transversely of the handle 10.

A locking disc 21 is secured to one end of a shaft 22 which is positioned through the opening. The peripheral edge 23 of the locking disc 21 is adapted to engage in the knurled edge 18 of the worm 16 and thereby hold the same against rotation. The other end of the shaft 22 has an enlarged shoulder 24 thereon and an adjacent head 25 is disposed on the opposite side of the handle 10 of the wrench with respect to the locking disc 21.

A coil spring 26 is disposed about the shaft 22 between the enlarged shoulder 24 thereon and the inner end of the larger portion 20 of the opening 19. The coil spring 26 biases the locking disc 21 toward the wrench handle 10 so that its peripheral edge is normally engaged against the knurled edge 18 of the adjustment worm 16.

The disposition of the locking disc 21 with respect to the axis of the adjustment worm 16 causes it to hold the worm 16 against rotation in either direction, although the Worm 16 can be forcibly moved in counterclockwise direction, as seen in Figure 3 of the drawing. In order to move it freely, it is only necessary for the workman to depress the button-like head 25 which will compress the coil spring 26' and move the locking disc 21 out of engagement with the worm 16 whereupon the same may be revolved and the wrench adjusted.

The construction disclosed herein is simple, easily formed and is positive in operation. It is operated by the normal actions of the workmans fingers in holding the wrench, the movement for operation, that is, in releasing the mechanism, being merely to depress the buttonlike head 25. Releasing the same, as is normal upon completing the adjustment of the wrench, again locks the adjustment worm 16.

It will thus be seen that the several objects of the invention have been met by the latch for a movable jaw wrench as disclosed herein.

Having thus described my invention, what I claim is:

l. A latching device for a movable jaw wrench comprising an elongated handle having an enlarged end portion terminating in a fixed jaw and having a pair of openings provided therein, one of said openings being rectangular and the other circular, a movable jaw provided with a rack portion slidably mounted in a channel in said end portion, and adjustment worm rotatably mounted in said rectangular opening and meshing with said rack portion of said movable jaw, the outermost edge of said worm having a continuous rack formed thereon, a shaft disposed in said circular opening and extending outwardly thereof on either side of said handle, a disc secured to one end of said shaft with the peripheral edge thereof normally engaged in said continuous rack on said worm, a

secondary disc secured to the other end of said shaft, a'

it the nds, ther qfi and a coil spring disposed about Said shaft go'sitioned between said shoulder and said secondary disc, said first-mentioned and secondary discs being normally spaced with respect to the sides of said handle and mov ble t war nd a ay hcr froms o. en a andisengage the, peripheral edge of said disc andsaid con; tinuous rack qf said worm and wherein the total length of said shaft includingthe discs on the opposite ends thereof isless than the thickest portion of said enlarged en por ion ofi sai Wren h- 1 7 2. The latching device for an adjustable wrench set iortlz in claimv 11 and wherein said disc and secondary disc are of different diameters, and wherein the largerdisc is engaged on said, worm.

References Cited in the file of this patent UNITED STATES PATENTS Nelson Nov. 15, 1881 Peloquin Jan. 17, 1905 McClurkin Feb. 1, 1921 Brown H Sept. 7, 1926 Schneider et a1. Mar. 4, 1930 Maguire May 31, 1932 Orchard Jan. 26, 1943 Lyons Aug. 2, 1955 Lyons v Feb. 5, 1955 

